1,323 research outputs found

    OSI in the NASA science internet: An analysis

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    The Open Systems Interconnection (OSI) protocol suite is a result of a world-wide effort to develop international standards for networking. OSI is formalized through the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). The goal of OSI is to provide interoperability between network products without relying on one particular vendor, and to do so on a multinational basis. The National Institute for Standards and Technology (NIST) has developed a Government OSI Profile (GOSIP) that specified a subset of the OSI protocols as a Federal Information Processing Standard (FIPS 146). GOSIP compatibility has been adopted as the direction for all U.S. government networks. OSI is extremely diverse, and therefore adherence to a profile will facilitate interoperability within OSI networks. All major computer vendors have indicated current or future support of GOSIP-compliant OSI protocols in their products. The NASA Science Internet (NSI) is an operational network, serving user requirements under NASA's Office of Space Science and Applications. NSI consists of the Space Physics Analysis Network (SPAN) that uses the DECnet protocols and the NASA Science Network (NSN) that uses TCP/IP protocols. The NSI Project Office is currently working on an OSI integration analysis and strategy. A long-term goal is to integrate SPAN and NSN into one unified network service, using a full OSI protocol suite, which will support the OSSA user community

    A Survey of Distributed Enterprise Network and Systems Management Paradigms

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    Since the mid 1990s, network and systems management has steadily evolved from centralized paradigms, where the management application runs on a single management station, to distributed paradigms, where it is distributed over many nodes. In this survey, our goal is to classify all these paradigms, especially the new ones, in order to help network and systems administrators design a management application, and choose between mobile code, distributed objects, intelligent agents, etc. Step by step, we build an enhanced taxonomy based on four criteria: the delegation granularity, the semantic richness of the information model, the degree of specification of a task, and the degree of automation of management

    Introduction to Directory Services

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    The Directory has grown to be an important OSI application as it acts as a focal point and general support for a number of other applications. This work first points out directory requirements in the OSI framework and other OSI applications, as the Mail Handling System. The first version of the X.500 standard is then described and some Directory related issues are discussed. In particular, X.500 Directory as a database system is examined and some directory service implementations are presented

    A conformance test framework for the DeviceNet fieldbus

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    The DeviceNet fieldbus technology is introduced and discussed. DeviceNet is an open standard fieldbus which uses the proven Controller Area Network technology. As an open standard fieldbus, the device conformance is extremely important to ensure smooth operation. The error management in DeviceNet protocol is highlighted and an error injection technique is devised to test the implementation under test for the correct error-recovery conformance. The designed Error Frame Generator prototype allows the error management and recovery of DeviceNet implementations to be conformance tested. The Error Frame Generator can also be used in other Controller Area Network based protocols. In addition, an automated Conformance Test Engine framework has been defined for realising the conformance testing of DeviceNet implementations. Automated conformance test is used to achieve consistent and reliable test results, apart from the benefits in time and personnel savings. This involves the investigations and feasibility studies in adapting the ISO 9646 conformance test standards for use in DeviceNet fieldbus. The Unique Input/Output sequences method is used for the generation of DeviceNet conformance tests. The Unique Input/Output method does not require a fully specified protocol specification and gives shorter test sequences, since only specific state information is needed. As conformance testing addresses only the protocol verification, it is foreseen that formal method validation of the DeviceNet protocol must be performed at some stage to validate the DeviceNet specification

    The InfoSec Handbook

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